Is lifespan determined in utero?

Low rates of growth in early life are now known to be associated with an increase in age related disease in later life.1 This is thought to reflect programming, the process whereby a stimulus or insult acting at a critical period of development in early life, has lasting or lifelong importance.2 In animal experiments that have examined the mechanisms responsible for programming, attention has focused on prenatal undernutrition and its influence on gene expression, cell division and differentiation, and tissue structure